Thanks for your feedback. > -----Original Message----- > From: Wood Scott-B07421 > Sent: Saturday, August 17, 2013 12:51 AM > To: Kumar Gala > Cc: Wang Dongsheng-B40534; linuxppc-dev@lists.ozlabs.org > Subject: Re: [PATCH 1/2] powerpc/85xx: add hardware automatically enter > altivec idle state > > On Fri, 2013-08-16 at 06:02 -0500, Kumar Gala wrote: > > On Aug 16, 2013, at 2:23 AM, Dongsheng Wang wrote: > > > > > From: Wang Dongsheng <dongsheng.w...@freescale.com> > > > > > > Each core's AltiVec unit may be placed into a power savings mode > > > by turning off power to the unit. Core hardware will automatically > > > power down the AltiVec unit after no AltiVec instructions have > > > executed in N cycles. The AltiVec power-control is triggered by > hardware. > > > > > > Signed-off-by: Wang Dongsheng <dongsheng.w...@freescale.com> > > > > Why treat this as a idle HW governor vs just some one time setup at > boot of the time delay? > > It is being done as one-time setup, despite the function name. > > Maybe it should be moved into __setup/restore_cpu_e6500 (BTW, we really > should refactor those to reduce duplication) with the timebase bit > number hardcoded rather than a time in us. > The frequency of the different platforms timebase is not the same. If we use it, we need to set different timebase bit on each platform. That is why I did not put the code in __setup/restore_cpu_e6500, I need use tb_ticks_per_usec to get timebase bit. So we only need to set a time for each platform, and not set different timebase bit.
> As for the PVR check, the upstream kernel doesn't need to care about > rev1, so knowing it's an e6500 is good enough. > But AltiVec idle & PW20 cannot work on rev1 platform. We didn't have to deal with it? -dongsheng _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
